High Performance Golf Ball Comprising Modified High Mooney Viscosity Rubber

ABSTRACT

A high performance golf ball made in part of a modified high Mooney viscosity rubber. The modified high Mooney viscosity rubber has less than about 20 phr oil and is high Mooney viscosity rubber having a Mooney viscosity at least about 40 blended with between about 1 phr and about 10 phr of process oil and between about 0.05 phr and 5 phr of peptizing agent.

BACKGROUND

The present disclosure relates generally to a golf ball comprisingmodified high Mooney viscosity rubber. The disclosure also relates to ahigh performance golf ball comprising the modified high Mooney viscosityrubber in a core layer.

Golf balls are important sporting goods that have changed with changesin technology. For example, balls were first made of wood, and then bystuffing boiled, softened feathers into a leather sack. The sacktypically was painted white, and would tighten upon drying. However,because the feather ball tended to absorb moisture and to split, manyballs were required to play a round. Also, these feather balls wereexpensive as compared with wooden balls.

Both feather and wooden balls were in use until the gutta percha ballwas made. The gutta percha ball was relatively inexpensive and easilymanufactured. Also, the gutta percha ball was fairly durable, ascompared with the feather ball, performed well because the surface couldeasily be roughened to improve flight characteristics, and so becamepopular. However, the ball exhibited a tendency to break up in flight.

Golf balls comprising other elastic materials then were developed. Forexample, a golf ball having a rubber core and an elastic thread woundtightly around the core was developed. The winding was covered withgutta percha at first, but later with balata. However, balata-coveredgolf balls often are damaged by players who are less skilled at strikingthe ball. Thus, tougher covers were developed, including in particularcovers comprising a Surlyn® compound or a polyurethane compound.

The interior structure of the golf ball has advanced, with plastics andpolymeric materials having properties and characteristics appropriatefor manufacture of high-quality, high-performance, affordable golfballs. In particular, polymeric materials having properties andcharacteristics appropriate for golf ball manufacture have beendeveloped. Such polymeric materials include polyurethanes and ionomericmaterials, including highly neutralized acid polymers. Blended materialsalso are used to manufacture other products.

However, the quest for such desirable golf balls sometimes is sabotagedby processing techniques that diminish the preferred properties andcharacteristics of the compositions used to form the golf ball. Forexample, high Mooney viscosity polybutadiene rubber has the propertiesand characteristics one would seek for a golf ball core, including inparticular, a high coefficient of restitution (COR). The high viscosityexhibited by high Mooney viscosity polybutadiene rubber makes itdifficult to process. Thus, significant stresses are placed onprocessing equipment, and the period required to process the high Mooneyviscosity polybutadiene rubber to form part of a golf ball, particularlypart of the core, is long.

A typical way to reduce the viscosity of high Mooney viscositypolybutadiene rubber is to incorporate oils and other materials toreduce the viscosity of the high Mooney viscosity polybutadiene rubber.Thus, extender oil and lubricant compositions often are added to highMooney viscosity rubber to ameliorate the difficulties in processing andforming. Typically, such compositions are added in large quantity, mosttypically greater than about 30 phr, and often as much as 500 phr.However, adding extender oil or such viscosity-reducing material in anamount sufficient to make processing appreciably easier, typicallygreater than about 30 phr, tends to reduce the COR and to degrade thedesired properties and characteristics of the rubber.

Other additives also have been used in an attempt to ameliorateprocessing and forming difficulties with high Mooney viscositypolybutadiene rubber without significantly degrading the performanceproperties and characteristics sought. For example, traditionalplasticizers such as phthalate esters have been utilized, but they areexpensive and sometimes difficulty compatible with high Mooney viscositypolybutadiene rubber. Similarly, fatty acids and metal soaps also areexpensive and tend not to adhere well, but rather exhibit ‘waxy’behavior.

Another type of composition often used as a core layer in a golf ball isthe highly neutralized polymer, or HNP. These materials have a high COR,but sometimes lack other properties and characteristics sought for golfball performance.

Therefore, there exists a need in the art for a high-performance golfball that includes components that are easily and efficiently processed.Such a golf ball exhibits high performance and can be produced withoutundue processing difficulty.

SUMMARY

In one aspect, the disclosure provides a golf ball that comprisesmodified high Mooney viscosity rubber.

In another aspect, the disclosure provides a high performance golf ballcomprising the modified high Mooney viscosity rubber in a core layer.

In yet another aspect, the disclosure provides a high performance golfball comprising both modified high Mooney viscosity rubber and HNP inseparate core layers.

In still another aspect, the disclosure provides a high performance golfball comprising both modified high Mooney viscosity rubber and HNP inseparate core layers and an HNP cover layer.

Other systems, methods, features, and advantages of the invention willbe, or will become, apparent to one of ordinary skill in the art uponexamination of the following figures and detailed description. It isintended that all such additional systems, methods, features andadvantages be included within this description and this summary, bewithin the scope of the invention, and be protected by the followingclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood with reference to the followingdrawings and description. The components in the figures are notnecessarily to scale, emphasis instead being placed upon illustratingthe principles of the invention. Moreover, in the figures, likereference numerals designate corresponding parts throughout thedifferent views.

FIG. 1 shows a representative golf ball in accordance with thisdisclosure, the golf ball being of a two-piece construction;

FIG. 2 shows a second representative golf ball, having a core, an innercover layer, and an outer cover layer;

FIG. 3 shows a third representative golf ball, having an inner core, anouter core layer, and a cover layer; and

FIG. 4 shows a fourth representative golf ball, having an inner core, anouter core layer, an inner cover layer, and an outer cover layer.

DETAILED DESCRIPTION

As used herein, unless otherwise stated, compression deformation,hardness, COR, flexural modulus, and Vicat softening temperature aremeasured as follows:

A. Compression deformation: The compression deformation herein indicatesthe deformation amount of the ball, or any portion thereof, under aforce; specifically, when the force is increased to become 130 kg from10 kg, the deformation amount of the ball or portion thereof under theforce of 130 kg reduced by the deformation amount of the ball or portionthereof under the force of 10 kg is the compression deformation value ofthe ball or portion thereof.

B. Hardness: Hardness of a golf ball layer is measured generally inaccordance with ASTM D-2240, but measured on the land area of a curvedsurface of a molded ball.

C. Method of measuring COR: A golf ball for test is fired by an aircannon at an initial velocity of 40 m/sec, and a speed monitoring deviceis located over a distance of 0.6 to 0.9 meters from the cannon. Thegolf ball strikes a steel plate positioned about 1.2 meters away fromthe air cannon and rebounds through the speed-monitoring device. Thereturn velocity divided by the initial velocity is the COR.

D. Flexural modulus: Measured in accordance with ASTM D-790.

E. Vicat softening temperature: Measured in accordance with ASTM D-1525.

F. Mooney viscosity is measured herein by a Mooney Shearing DiskViscometer in accordance with ASTM D1646. The viscometer is run at adefined temperature, which is 100° C. herein. The resultant value,identified as (ML₁₊₄ (100° C.)) and expressed as a number, is anindication of the torque on the viscometer's rotating spindle withinheated dies.

G. Compression often is measured with a device from ADC, and typicallyis reported in millimeters (mm). An ADC compression tester, commerciallyavailable from Automated Design Corp. in Illinois, USA, can be used tocarry out this determination. The ADC compression tester can be set toapply a first load and obtain a first deformation amount, and then,after a selected period, to apply a second, typically higher load anddetermine a second deformation amount. Thus, the first load herein is 10kg, the second load herein is 130 kg, and the compression deformation isthe difference between the second deformation and the first deformation.Herein, this distance is reported in millimeters. The compression can bereported as a distance, or as an equivalent to other deformationmeasurement techniques, such as Atti compression.

The disclosure provides a golf ball that comprises modified high Mooneyviscosity rubber. In particular, the disclosure provides a highperformance golf ball comprising the modified high Mooney viscosityrubber in a core layer.

High Mooney viscosity rubber is defined herein as a rubber having aMooney viscosity value of at least about 40, typically at least about50. In embodiments of the disclosure, high Mooney viscosity rubber ismodified by addition of less than about 10 phr (pounds per hundredpounds of rubber) of process oil and less than about 5 phr peptizingagent to form modified high Mooney viscosity rubber.

High Mooney viscosity rubber has desirable properties andcharacteristics for use in golf balls. For example, high Mooneyviscosity rubber has high COR, low cold flow, and higher molecularweight. Low cold flow and high molecular weight imbue the high Mooneyviscosity rubber with excellent durability. However, high Mooneyviscosity rubber typically is difficult to process because both mixingand extruding are difficult. Also, forming a golf ball layer from highMooney viscosity rubber typically is difficult because molding highMooney viscosity rubber typically is difficult.

The inventors have discovered that it is possible to use only smallamounts of process oil, i.e., less than about 10 phr, in combinationwith less than about 5 phr peptizing agent to yield modified high Mooneyviscosity rubber. The inventors have discovered that this combinationprovides processing and forming advantages over unmodified high Mooneyviscosity rubber while maintaining most of the sought-after propertiesand characteristics, particularly COR. Importantly, the inventors alsohave discovered that judicious use of a combination of modified highMooney viscosity rubber and HNP in separate core layers provides a golfball core that yields excellent COR and a high performance golf ballthat can be made with reduced processing difficulty.

In yet another aspect, therefore, the disclosure provides a highperformance golf ball comprising both modified high Mooney viscosityrubber and HNP in separate core layers. The HNP further ameliorates thereduction in COR caused by addition of the process oil and providesadditional hardness and resilience to the core layers.

In still another aspect, the disclosure provides a high performance golfball comprising both modified high Mooney viscosity rubber and HNP inseparate core layers and an HNP cover layer. The HNP cover layerprovides not only high performance spin control and an excellent flightpath, but also excellent scuff resistance.

In yet another aspect, the disclosure provides a high performance golfball comprising both modified high Mooney viscosity rubber and HNP inseparate core layers and a polyurethane cover. Further, the polyurethanecover may be cross-linked or otherwise treated to provide scuffresistance.

The disclosure relates to golf balls having 2 or more layers. If thegolf ball has only 2 layers, the core is modified high Mooney viscosityrubber and the cover is HNP. However, it is more typical for golf ballsthat benefit from this disclosure to have at least 3 layers.

FIG. 1 illustrates a 2-layer or 2-piece golf ball 100 having core 120essentially surrounded by cover layer 110. In this golf ball embodiment,core 120 comprises modified high Mooney viscosity rubber and cover layer110 comprises HNP or another suitable cover material, such aspolyurethane.

FIG. 2 illustrates a 3-piece golf ball 200 having a relatively largecore 230 essentially surrounded by inner cover layer 220, which itselfis encompassed within or essentially surrounded by outer cover layer210. In this golf ball embodiment, core 230 comprises modified highMooney viscosity rubber, inner cover layer 220 typically comprises HNP,and outer cover layer 210 comprises HNP (whether the same as ordifferent from the HNP used in inner cover layer 220), polyurethane, oranother cover layer material.

FIG. 3 illustrates 3-piece golf ball 300 having a relatively smallerinner core 330, outer core layer 320, and cover layer 310. In this golfball embodiment, inner core 330 comprises modified high Mooney viscosityrubber, outer core layer 320 typically comprises HNP, and cover layer310 comprises HNP (whether the same as or different from the HNP used ininner cover layer 320), polyurethane, or another cover layer material.

FIG. 4 illustrates 4-piece golf ball 400 having inner core 440, outercore layer 430, inner cover layer 420, and outer cover layer 410. Inthis golf ball embodiment, inner core 440 comprises modified high Mooneyviscosity rubber, outer core layer 430 typically comprises HNP, andcover layers 420 and 410 comprise other cover layer materials, such asHNPs, ionomers, polyurethane, and other materials. In another golf ballembodiment, inner core 440 comprises typical core material, includingmodified high Mooney viscosity rubber, outer core layer 430 typicallycomprises HNP, inner cover layer 420 comprises modified high Mooneyviscosity rubber, and outer cover layer 410 comprise other cover layermaterials, such as HNPs, ionomers, polyurethane, and other materials.

Thus, in embodiments of the disclosure, modified high Mooney viscosityrubber typically is used in the inner core, but also can be used in theouter core layer, if present, and in the inner cover layer, if present.Modified high Mooney viscosity rubber also can be used in two layers ofthe same golf ball. Typically, modified high Mooney viscosity rubber isnot used as outer cover material because of the tendency of the processoil to bloom and become separated from the high Mooney viscosity rubber.There are materials, such as maleic anhydride, silanes, and titanates,that can be used to compatibilize the process oil and the high Mooneyviscosity rubber. However, the separation tendency typically is bettermanaged, and more easily managed, in a layer that is essentiallyencompassed within another layer.

In embodiments of the disclosure, modified high Mooney viscosity rubbercomprises high Mooney viscosity rubber blended with process oil and apeptizing agent. Although the inventors do not wish to be bound bytheory, it is believed that process oils aid the processing and formingof the rubber by serving as a physical peptizer that reduces viscositywithout shortening rubber chain length. Further, it is believed that apeptizing agent acts as a chemical peptizer, shortening chain length byscission to reduce viscosity. Process oils are present at less thanabout 10 phr, typically between about 1 phr and about 9 phr, moretypically between about 2 phr and about 8 phr, and most typicallybetween about 2 phr and 7.5 phr. Peptizing agents are present in anamount between about 0.01 phr and about 5.0 phr, typically between about0.1 phr and about 4 phr, and more typically between about 0.2 phr andabout 1 phr.

The quantity of oil disclosed herein is in addition to any oils orsimilar lubricious materials that may have been added to the high Mooneyviscosity rubber as a component of or carrier for another compound. Forexample, the skilled practitioner recognizes not only that rubber mayhave a small amount of extender oil in it as supplied, but also thatsome ingredients, additives, and modifiers may be supplied in oil orassociated with oil. Typically, such materials are pulverulentcompositions, and the amount of oil so supplied is relatively small andproduces no adverse effects in the finished product. However, thepotential exists for introducing amounts that, when accumulated, exceedthat amount of oil that may produce adverse effects in finished product.

For example, the skilled practitioner is familiar with the Crystex®family of sulfur delivery products. These products comprise sulfur andoil in quantities between about 10 wt percent and 30 wt percent, basedon the weight of the Crystex® product. Although the inventors do notwish to be bound by theory, it is believed that this oil serves both tosuppress the tendency of pulverulent sulfur to fly into the air, causinga potential health and safety hazard, and to aid in dispersion of thesulfur in the rubber. Whereas the skilled practitioner recognizes thatthis sulfur-containing product typically is not used in rubber to beused in the manufacture of golf balls, Crystex® is a well-known productthat exemplifies this type of product. Oil may be introduced as adispersant and as a dust-reducing composition in conjunction with sulfurand other pulverulent solids or other materials that are difficult toblend with or disperse in rubber or tend to become dispersed in air.Thus, this oil often is called ‘dispersant oil’. Also, the rubber may be‘extended’ rubber, i.e., rubber already containing extender oil.

In embodiments of the disclosure, the total amount of oil in rubber,i.e., the sum of process oil, dispersant oil, and extender oil alreadypresent in the rubber, is less than about 20 phr, typically betweenabout 1 phr and about 18 phr, and more typically between about 2 phr andabout 15 phr. The amount of process oil is less than about 10 phr, andtypically is between about 1 phr and about 9 phr in embodiments of thedisclosure. In other embodiments of the disclosure, process oil moretypically is between about 2 phr and about 8 phr, most typically betweenabout 2 phr and about 7.5 phr. Further, the amount of dispersant oil andextender oil present typically is less than about 10 phr. If the amountof these oils exceeds about 10 phr, the maximum amount of process oilintroduced in embodiments of the disclosure typically is limited to thatamount that will ensure that the total amount of oil does not exceedabout 20 phr. With the guidance provided herein, the skilledpractitioner will be able to select components of the rubber that limitthe amount of oil present in the rubber.

In this disclosure, high Mooney viscosity rubber is defined as rubberhaving Mooney viscosity greater than about 40, or greater than about 50,or greater than about 55, or greater than about 60, or greater thanabout 65, or greater than about 70. Mooney viscosity is measured as setforth in the definitions.

High Mooney viscosity rubber is selected from the group consisting ofpolybutadiene rubber, polyisoprene rubber, natural rubber, ethylenepropylene rubber, ethylene propylene diene rubber, styrene-butadienerubber, and blends thereof, that have Mooney viscosity value greaterthan about 40, or greater than about 50, or greater than about 55, orgreater than about 60, or greater than about 65, or greater than about70. In embodiments of the disclosure, the high Mooney viscosity rubbercomprises, in major part, polybutadiene rubber. For convenience herein,the disclosure will focus on high Mooney viscosity polybutadiene rubber,and the modified high Mooney viscosity polybutadiene rubber resultingtherefrom upon addition of process oil and peptizing agent.

In embodiments of the disclosure, the high Mooney viscositypolybutadiene rubber comprises high-cis high Mooney viscositypolybutadiene rubber, typically neodymium-catalyzed polybutadienerubber. Cobalt-catalyzed and nickel-catalyzed versions also aresuitable.

The skilled practitioner recognizes that polybutadiene rubber isavailable in various versions, including high-cis (greater than about 92percent cis structure, typically with less than about 4 percent transand less than about 4 percent vinyl); low-cis (as little as about 35percent cis structure) and vinyl, all of which structures is suitable inembodiments of the disclosure.

Typically, high-cis high Mooney viscosity polybutadiene rubber is usedin accordance with the disclosure herein. Polybutadiene having primarilytrans structure is not an elastic product, but rather is a crystalline,plastic product. Therefore, polybutadiene comprising primarily transstructure typically is not used as a rubber (elastic) product and sowould not be suitable for use in this disclosure, although small amountsof crystalline trans polybutadiene in elastomeric polybutadiene rubberare to be expected, and do not adversely affect the properties andcharacteristics of the elastic polybutadiene rubber product.

In embodiments of the disclosure, members of the Buna CB family orseries of polybutadiene rubber having a Mooney viscosity greater thanabout 50, available from Lanxess USA, Texas, USA, are suitably used. Inparticular, Buna CB 21, a highly linear neodymium-catalyzed butadienerubber having a Mooney viscosity of 73; Buna CB 22 and Buna Nd 60, eacha highly linear neodymium-catalyzed butadiene rubber having a Mooneyviscosity of 63, and Buna CB 1221, a branched cobalt-catalyzed butadienerubber having a Mooney viscosity of 53, are suitable in embodiments ofthe disclosure.

Other high Mooney viscosity polybutadiene rubbers suitable for use inembodiments of the disclosure include LG BR1208, which has a Mooneyviscosity of 40 and is available from LG Chem, LTD, Korea, and Kumho 60,which has a Mooney viscosity of 60 and is available from Kumho, Korea.

The high Mooney viscosity polybutadiene rubber typically is cured usinga conventional curing process. Suitable curing processes include, forexample, peroxide curing, radiation curing, and combinations thereof.

In one embodiment, the high Mooney viscosity polybutadiene rubber isperoxide cured. Organic peroxides suitable as free radical initiatorsinclude, for example, dicumyl peroxide (DCP);n-butyl-4,4-di(t-butylperoxy)valerate;1,1-di(t-butylperoxy)3,3,5-trimethylcyclohexane (TMCH);2,5-dimethyl-2,5-di(t-butylperoxy)hexane; di-t-butyl peroxide; di-t-amylperoxide; t-butyl peroxide; t-butyl cumyl peroxide;2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3;di(2-t-butyl-peroxyisopropyl)benzene; dilauroyl peroxide; dibenzoylperoxide; t-butyl hydroperoxide; and combinations thereof. Peroxide freeradical initiators are generally present in the rubber compositions inan amount within the range having a lower limit of 0.05 phr, or 0.1 phr,or 0.25 phr, or 1 part, or 1.5 phr, and an upper limit of 2.5 phr, or 3phr, or 5 phr, or 6 phr, or 10 phr, or 15 phr.

Co-agents can be used with peroxides to improve the cure. Suitableco-agents include, for example, metal salts of unsaturated carboxylicacids having from 3 to 8 carbon atoms; unsaturated vinyl compounds andpolyfunctional monomers (for example, trimethylolpropanetrimethacrylate); phenylene bismaleimide; and combinations thereof.Particularly suitable metal salts include, for example, one or moremetal salts of acrylates, diacrylates, methacrylates, anddimethacrylates, wherein the metal is selected from magnesium, calcium,zinc, aluminum, lithium, and nickel. In a particular embodiment, theco-agent is selected from zinc salts of acrylates, diacrylates,methacrylates, and dimethacrylates. In another particular embodiment,the co-agent is zinc diacrylate (ZDA). When the agent is zinc diacrylateand/or zinc dimethacrylate, the co-agent is typically included in therubber composition in an amount within the range having a lower limit of1 phr, or 5 phr, or 10 phr, or 20 phr, and an upper limit of 25 phr, or30 phr, or 35 phr, or 40 phr, or 50 phr, or 60 phr. When one or moreless active co-agents are used, such as zinc monomethacrylate andvarious liquid acrylates and methacrylates, the amount of less activeco-agent used may be the same as or higher than for zinc diacrylate andzinc dimethacrylate co-agents.

High energy radiation sources capable of generating free radicals mayalso be used to crosslink the high Mooney viscosity polybutadienerubber. Suitable examples of such radiation sources include, forexample, electron beams, ultra-violet radiation, gamma radiation, X-rayradiation, infrared radiation, heat, and combinations thereof. Freeradical initiators known in the art also may be used.

With the guidance provided herein, the skilled practitioner will be ableto select a curing agent or combinations thereof to cure the high Mooneyviscosity polybutadiene rubber.

Other compositions may be added to the high Mooney viscositypolybutadiene rubber. For example, a cis-to-trans conversion compound,such as halogenated organosulfur compounds, may be added. Anti-oxidantcompounds also may be present. The skilled practitioner is familiar withthese compounds and can select suitable compounds and the amount thereofto provide the desired result.

Further, as described above, the disclosure relates to golf balls havingat least 2 layers, or pieces. Thus, although discussion herein isdirected to a 4-piece ball for convenience, the disclosure is directedto golf balls having at least 2-layers, and as many as 5, 6, or 7layers, or more. The number of layers in the golf ball is limited onlyby any rules extant at the time of manufacture if the ball is to be“conforming,” i.e., meet the rules of a governing body such as the USGA.

Process oil added to the high Mooney viscosity polybutadiene rubber isselected from the group consisting of process oils, vegetable oils,vulcanized or functionalized vegetable oils, oils from animals,functionalized oils, and blends thereof. Typically, process oil isselected from the group consisting of process oils, vegetable oils,functionalized vegetable oils, and blends thereof. More typically,process oil is vegetable oil, functionalized vegetable oil, and blendsthereof.

Suitable process oils include, for example, aromatic oils, naphthenicoils, and paraffinic oils, as classified by ASTM D2226. As the skilledpractitioner recognizes, such oils typically are a blend of aromatic,naphthenic, and paraffinic oils, and are classified by the predominanttypes of properties and characteristics of the oil. In an embodiment,the process oil is selected from paraffinic oil, naphthenic oil, andblends thereof. Aromatic oils lower viscosity more than the samequantity of naphthenic oil or paraffinic oil, but may cause concern overpotential health threats.

Aromatic oils include the Sundex® family of aromatic oils available frommany sources, including American Lubricants & Chemicals, LLC, in Ohio,USA. Particularly suitable paraffinic and naphthenic oils include, forexample, Sunpar® paraffinic oil, a family of oils commercially availablefrom Sunoco, Inc. of Pennsylvania, USA and HollyFrontier Refining andMarketing; Paralux® paraffinic oil, a family of oils commerciallyavailable from Chevron Corporation of California, USA; Unithene®naphthenic oil, a family of oils commercially available from Ergon, Inc.of Mississippi, USA; and the family of oils commercially available fromIdemitsu USA under the name Diana Process Oil PS.

In some embodiments, suitable oils also include low PCA/PHA (polycyclicaromatic/polyaromatic hydrocarbon) oils, including mild extractionsolvates (MES), treated distillate aromatic extracts (TDAE), and heavynaphthenic oils. Suitable low PCA oils are further disclosed in U.S.Pat. No. 6,977,276 (column 4, line 31 up to and including column 6, line27), the entire disclosure of which is hereby incorporated herein byreference. Hydrogenated naphthenic oils, including those disclosed inU.S. Pat. No. 6,939,910, the entire disclosure of which is herebyincorporated herein by reference, also are suitable in some embodiments.

Suitable vegetable oils for use in embodiments of the disclosureinclude, for example, rapeseed oil, castor oil, linseed oil, soybeanoil, and tung oil. Suitable vulcanized vegetable oils include, forexample, semi-translucent factice, black factice, and brown factice; inparticular, “F14” and “F17” sulfur vulcanized rapeseed oils, “K14D”sulfur vulcanized modified fatty acids, “Gloria 17” sulfur vulcanizedrapeseed oil, “Hamburg 4” partially hydrogenated rapeseed oil, and “WP”peroxide crosslinked modified castor oil free of sulfur and chlorine,all of which are commercially available from R.T. Vanderbilt Company,Inc. of Norwalk, Conn.

Embodiments of the disclosure also use functionalized vegetable oil.Functionalized vegetable oils include, for example, epoxidized soy beanoil, epoxidized linseed oil, and epoxidized alkyl oils. One suitableepoxidized soy bean oil family is available from Arkema Inc., ofPennsylvania, USA, under the tradename Vikoflex®. Functionalizedvegetable oils also include the reaction product of an epoxidized oilwith a peroxide, an amine, a polyamide, or an isocyanate-containingmolecule. Although the inventors do not wish to be bound by theory,epoxidized oil and functionalized oils can be incorporated into thepolymeric structure of the modified high Mooney viscosity polybutadienerubber. In any event, functionalized oils exhibit significantly lessmotility of the oil, thus reducing blooming of the oil, i.e., reducingseparation of the oil from the modified high Mooney viscositypolybutadiene rubber.

Functionalizing moieties typically are present in an amount betweenabout 0.5 phr and 10 phr, more typically between about 1 phr and 5 phr,and even more particularly between about 1.25 and 3 phr. Also, thefunctionalizing moiety typically comprises between about 5 wt percentand about 20 wt percent, based on the weight of the functionalized oil,more typically between about 8 wt percent and about 12 wt percent, basedon the weight of the functionalized oil.

Suitable oils from animals include, for example, whale oil and fish oil.

In embodiments of the disclosure, suitable peptizing agents includecompositions that contain an organic sulfur compound and/or ametal-containing organic sulfur compound in addition to the base rubberand the unsaturated carboxylic acid metal salt. Examples of the organicsulfur compound include thiophenols such as pentachlorothiophenol,4-butyl-o-thiocresol, 4-t-butyl-p-thiocresol, and 2-benzamidothiophenol,thiocarboxylic acids such as thio-benzoic acid, and sulfides such asdixylyl disulfide, di(o-benzamidophenyl)disulfide and alkylated phenolsulfides. Examples of the metal-containing organic sulfur compoundinclude zinc salts of the above-mentioned thiophenols and thiocarboxylicacids. The sulfur compounds may be used alone or in admixture of two ormore. The sulfur compound is preferably blended in amounts of from about0.05 to about 2 parts by weight, more preferably from about 0.1 to about0.5 parts by weight per 100 parts by weight of the base rubber.

Typically, the peptizing agents are known conventionally as “soft andfast” agents. The conventional soft and fast agent is present in anamount within a range having a lower limit of about 0.05 phr or about0.1 phr or about 0.2 phr or about 0.5 phr and an upper limit of about0.05 phr or about 1 phr or about 2 phr or about 3 phr or about 5 phr. Asused herein, “soft and fast agent” means any compound or a blend thereofthat is capable of making a core softer (have a lower compression) at aconstant COR, making a core faster (have a higher COR at equalcompression), or a combination thereof, when compared to a coreequivalently prepared without a soft and fast agent. Suitableconventional soft and fast agents include, but are not limited to, thoseselected from organosulfur and metal-containing organosulfur compounds,organic sulfur compounds, including mono-, di-, and poly-sulfides,thiol, and mercapto compounds, inorganic sulfide compounds, Group VIAcompounds, substituted or unsubstituted aromatic organic compounds thatdo not contain sulfur or metal, aromatic organometallic compounds, andmixtures thereof.

Additional suitable soft and fast agents, or peptizing agents, includeorganosulfur compounds, such as the thiophenols, includingpentafluorothiophenol; 2-fluorothiophenol; 3-fluorothiophenol;4-fluorothiophenol; 2,3-fluorothiophenol; 2,4-fluorothiophenol;3,4-fluorothiophenol; 3,5-fluorothiophenol 2,3,4-fluorothiophenol;3,4,5-fluorothiophenol; 2,3,4,5-tetrafluorothiophenol;2,3,5,6-tetrafluorothiophenol; 4-chlorotetrafluorothiophenol;pentachlorothiophenol; 2-chlorothiophenol; 3-chlorothiophenol;4-chlorothiophenol; 2,3-chlorothiophenol; 2,4-chlorothiophenol;3,4-chlorothiophenol; 3,5-chlorothiophenol; 2,3,4-chlorothiophenol;3,4,5-chlorothiophenol; 2,3,4,5-tetrachlorothiophenol;2,3,5,6-tetrachlorothiophenol; pentabromothiophenol; 2-bromothiophenol;3-bromothiophenol; 4-bromothiophenol; 2,3-bromothiophenol;2,4-bromothiophenol; 3,4-bromothiophenol; 3,5-bromothiophenol;2,3,4-bromothiophenol; 3,4,5-bromothiophenol;2,3,4,5-tetrabromothiophenol; 2,3,5,6-tetrabromothiophenol;pentaiodothiophenol; 2-iodothiophenol; 3-iodothiophenol;4-iodothiophenol; 2,3-iodothiophenol; 2,4-iodothiophenol;3,4-iodothiophenol; 3,5-iodothiophenol; 2,3,4-iodothiophenol;3,4,5-iodothiophenol; 2,3,4,5-tetraiodothiophenol;2,3,5,6-tetraiodothiophenol; zinc salts thereof; non-metal saltsthereof, for example, ammonium salt of pentachlorothiophenol; magnesiumpentachlorothiophenol; cobalt pentachlorothiophenol; and combinationsthereof.

Suitable metal-containing organosulfur compounds include, but are notlimited to, cadmium, copper, lead, and tellurium analogs ofdiethyldithiocarbamate, diamyldithiocarbamate, anddimethyldithiocarbamate, and combinations thereof. Additional examplesare disclosed in U.S. Pat. No. 7,005,479, the entire disclosure of whichis hereby incorporated herein by reference.

Suitable disulfides include, but are not limited to, 4,4′-diphenyldisulfide; 4,4′-ditolyl disulfide; 4,4′-dixylyl disulfide;2,2′-benzamido diphenyl disulfide; bis(2-aminophenyl)disulfide;bis(4-aminophenyl)disulfide; bis(3-aminophenyl)disulfide;2,2′-bis(4-aminonaphthyl)disulfide; 2,2′-bis(3-aminonaphthyl)disulfide;2,2′-bis(4-aminonaphthyl)disulfide; 2,2′-bis(5-aminonaphthyl)disulfide;2,2′-bis(6-aminonaphthyl)disulfide; 2,2′-bis(7-aminonaphthyl)disulfide;2,2′-bis(8-aminonaphthyl)disulfide; 1,1′-bis(2-aminonaphthyl)disulfide;1,1′-bis(3-aminonaphthyl)disulfide; 1,1′-bis(3-aminonaphthyl)disulfide;1,1′-bis(4-aminonaphthyl)disulfide; 1,1′-bis(5-aminonaphthyl)disulfide;1,1′-bis(6-aminonaphthyl)disulfide; 1,1′-bis(7-aminonaphthyl)disulfide;1,1′-bis(8-aminonaphthyl)disulfide;1,2′-diamino-1,2′-dithiodinaphthalene;2,3′-diamino-1,2′-dithiodinaphthalene; bis(4-chlorophenyl)disulfide;bis(2-chlorophenyl)disulfide; bis(3-chlorophenyl)disulfide;bis(4-bromophenyl)disulfide; bis(2-bromophenyl)disulfide;bis(3-bromophenyl)disulfide; bis(4-fluorophenyl)disulfide;bis(4-iodophenyl)disulfide; bis(2,5-dichlorophenyl)disulfide;bis(3,5-dichlorophenyl)disulfide; bis(2,4-dichlorophenyl)disulfide;bis(2,6-dichlorophenyl)disulfide; bis(2,5-dibromophenyl)disulfide;bis(3,5-dibromophenyl)disulfide; bis(2-chloro-5-bromophenyl)disulfide;bis(2,4,6-trichlorophenyl)disulfide;bis(2,3,4,5,6-pentachlorophenyl)disulfide; bis(4-cyanophenyl)disulfide;bis(2-cyanophenyl)disulfide; bis(4-nitrophenyl)disulfide;bis(2-nitrophenyl)disulfide; 2,2′-dithiobenzoic acid ethylester;2,2′-dithiobenzoic acid methylester; 2,2′-dithiobenzoic acid;4,4′-dithiobenzoic acid ethylester; bis(4-acetylphenyl)disulfide;bis(2-acetylphenyl)disulfide; bis(4-formylphenyl)disulfide;bis(4-carbamoylphenyl)disulfide; 1,1′-dinaphthyl disulfide;2,2′-dinaphthyl disulfide; 1,2′-dinaphthyl disulfide;2,2′-bis(1-chlorodinaphthyl)disulfide;2,2′-bis(1-bromonaphthyl)disulfide; 1,1′-bis(2-chloronaphthyl)disulfide;2,2′-bis(1-cyanonaphthyl)disulfide; 2,2′-bis(1-acetylnaphthyl)disulfide;and the like; and combinations thereof.

Suitable inorganic sulfide compounds include, but are not limited to,titanium sulfide, manganese sulfide, and sulfide analogs of iron,calcium, cobalt, molybdenum, tungsten, copper, selenium, yttrium, zinc,tin, and bismuth.

In particular, as noted herein, especially suitable peptizing agents, orsoft and fast agents, for use in embodiments of the disclosure include,but are not limited to, zinc pentachlorothiophenol,pentachlorothiophenol, ditolyl disulfide, diphenyl disulfide, dixylyldisulfide, and mixtures thereof. The soft and fast agent component mayalso be a blend of an organosulfur compound and an inorganic sulfidecompound.

Typically, the halogenated thiophenol peptizing agent ispentachlorothiophenol, which is commercially available in salt or neatform, or under the tradename STRUKTOL®, a clay-based carrier containing,in one form, pentachlorothiophenol (PCTP) loaded at 45 percent.STRUKTOL® is commercially available from Struktol Company of America ofOhio. PCTP is commercially available in neat form and in the zinc saltform from eChinachem of California, US. Suitable organosulfur compoundsare further disclosed, for example, in U.S. Pat. Nos. 6,635,716,6,919,393, 7,005,479 and 7,148,279, the entire disclosures of which arehereby incorporated herein by reference.

Further, in embodiments of the disclosure, activators may be used toaccelerate peptization by starting the process at a lower temperature.Activators are chelates, or complexes, of ketoxime, phthalocyanine, oracetylacetone with metals such as iron, cobalt, nickel, or copper.Typically, the metal is iron. Because these activator compounds(chelates, or complexes) are highly effective, only small amounts arepresent with the peptizing agent.

The process oil and peptizing agent are mixed with high Mooney viscositypolybutadiene rubber to form modified high Mooney viscositypolybutadiene rubber in any suitable way. In some embodiments of thedisclosure, the process oil, peptizing agent, and high Mooney viscositypolybutadiene rubber are kneaded or melt-blended in any suitable manner.Suitable equipment for blending the high Mooney viscosity polybutadienerubber with the process oil and peptizing agent in accordance with thisdisclosure includes a twin screw extruder, a Banbury-type mixer, atwo-roll mill (also known as a two-roll sheeter), or another manner ofkneading the fairly stiff high Mooney viscosity polybutadiene rubberwith the oil. Typically, kneading with a Banbury-type mixer, a two-rollmill, or any suitable kneading device is used to blend process oil andpeptizing agent with high Mooney viscosity polybutadiene rubber.

In embodiments of the disclosure, the components are heated beforeintroducing each to the kneader, two-roll mill, or other mixing device.The high Mooney viscosity polybutadiene rubber should be heated to atemperature below the scorch point, and the process oil should be heatedto a temperature below the smoke point. The peptizing agent also can beheated, as appropriate. In this way, the time and significant energyinput required for mixing the components will be reduced withoutreducing the quality of the product.

In embodiments of the disclosure, the modified high Mooney viscositypolybutadiene rubber is used in parts of a golf ball having at least 2layers, typically in a golf ball having at least 3 layers, or pieces,and more typically in a golf ball having at least 4 layers. Typically,modified high Mooney viscosity polybutadiene rubber of the disclosureforms the core of a golf ball having at least 3 layers, or pieces, suchas in core 230 of golf ball 200; core 330 of golf ball 300; and core 440of golf ball 400. Embodiments of the disclosure also include golf ballshaving a core comprising modified high Mooney viscosity polybutadienerubber and having 5 or more layers.

The inventors have discovered that substantially enclosing orsubstantially encompassing the modified high Mooney viscositypolybutadiene rubber core with a layer of HNP is particularly effectivein forming a core or golf ball portion that has high COR. Thus,embodiments of the disclosure having a core comprising modified highMooney viscosity polybutadiene rubber in the core advantageously have acover 110 (two-piece), inner cover 220 (three-piece), outer core 320(three-piece), or inner cover 430 (four-piece) comprising an HNP.

HNPs suitable for use in embodiments of the disclosure include highlyneutralized terpolymer ionomers. HPF resins such as HPF1000, HPF2000,HPF AD1024, HPF AD1027, HPF AD1030, HPF AD1035, HPF AD1040, and othermembers of the HPF family of HNPs produced by E. I. DuPont de Nemoursand Company, are exemplary of HNPs suitably used in embodiments of thedisclosure. With the guidance provided herein, the skilled practitionerwill be able to identify suitable HNPs to use to substantially encompassa core comprising modified high Mooney viscosity polybutadiene rubberdisclosed herein.

Modified high Mooney viscosity polybutadiene rubber of embodiments ofthe disclosure also can be used to form an outer core layer (320 or 430)or an inner cover layer (220 or 420), also known as a mantle layer.Because the modified high Mooney viscosity polybutadiene rubber isdense, a thin inner cover layer may be useful in controlling spin andproviding a high MOI golf ball.

For any arrangement of layers not specifically mentioned herein, anylayer may be made of any material suitable for the purpose. For example,an outer cover layer should be tough and resistant to scuffing. Thus,thermoplastic polyurethane (TPU) and thermoset polyurethane are suitablefor use in outer cover layers, as are HNP and ionomers. Thermoplasticpolyurethane that is not scuff resistant without more can be treated toharden the surface, such as by a surface treatment. Suitable ionomersinclude members of the Surlyn® family of ionomeric polymers produced byE. I. DuPont de Nemours and Company and members of the Lotek® family ofproducts produced by ExxonMobil Chemical Corporation.

The inventors also have discovered that modified high Mooney viscositypolybutadiene rubber of this disclosure can be blended with HNP to forma blended material that can be used in any layer the modified highMooney viscosity polybutadiene rubber can be used. The blend has a highCOR and is therefore particularly suited to serve as a core,particularly as an outer core, in a high performance golf ball. Theblend may have a slightly higher density than the modified high Mooneyviscosity polybutadiene rubber, and therefore also may form a suitablemantle (inner cover) layer.

The relative weight proportions of the modified high Mooney viscositypolybutadiene rubber to HNP in a blended product range from about 60:40to about 99.5:0.5, typically from about 70:30 to about 99:1, and moretypically from about 75:25 to about 99:1.

The modified high Mooney viscosity polybutadiene rubber and the HNP canbe mixed in the same way the modified high Mooney viscositypolybutadiene rubber is made, i.e., on a two-roll sheeter or otherkneading device. A compatibilizer or linker for the rubber and the HNPlikely would be required to form a coherent blend of these components.

The modified high Mooney viscosity polybutadiene rubber disclosedherein, and the blend of modified high Mooney viscosity polybutadienerubber with HNP, also may be suitably used as an outer cover layer. Ifthe modified high Mooney viscosity polybutadiene rubber or the blend isused as an outer cover layer, it is typical to ensure that the processoil does not ‘bloom’ and separate from the high Mooney viscositypolybutadiene rubber. In that case, and in any other circumstance inwhich it is important to maintain excellent compatibility, acompatibilizer can be employed.

Compatibilizers include maleic anhydride, silanes, and titanates. Theskilled practitioner recognizes that the silanes have the generalformula Si_(n)H_(2n+2). Typically, n is less than about 8, as largermolecules are only difficulty made. The titanates are compounds known tothe skilled practitioner. For example, the Ken-React® family of titanatecoupling agents, available from Kenrich Petrochemical, Inc., of NewJersey, USA, are suitable titanates. Suitable titanates includemonoalkoxy titanates, such as KR® TTS (Titanium IV 2-propanolato, trisisooctadecanoato-O) and KR 7 (Titanium IV bis 2-methyl-2-propenoato-O,isooctadecanoato-O 2-propanolato); oxyacetate chelate titanates, such asKR® 134S (Titanium IV bis[4-(2-phenyl)-2-propyl-2]phenolato,oxoethylenediolato) and KR 138S (Titanium IVbis(dioctyl)pyrophosphato-O, oxoethylenediolato, (adduct),(dioctyl)(hydrogen)phosphite); A,B ethylene chelate titanates, such asKR® 212 (Titanium IV bis(dioctyl)phosphato-O, ethylenediolato) and KR238S (Titanium IV bis(dioctyl)pyrophosphato-O, ethylenediolato (adduct),bis(dioctyl)hydrogen phosphite); quaternary titanates, such as KR® 138D(Titanium IV bis(dioctyl)pyrophosphato-O, oxoethylenediolato, (adduct) 2moles of 2-N,N-dimethylamino-2-methylpropanol) and KR 158D (Titanium IVbis(butyl methyl)pyrophosphato-O, (adduct) 2 moles2-N,N-dimethylamino-2-methylpropanol); coordinate titanates, such as KR®41B (Titanium IV tetrakis 2-propanolato, adduct 2 moles(dioctyl)hydrogen phosphate) and KR 46B (Titanium IV tetrakis octanolatoadduct 2 moles (di-tridecyl)hydrogen phosphite); neoalkoxy titanates,such as LICA® 01 (Titanium IV 2,2(bis 2-propenolatomethyl)butanolato,tris neodecanoato-O) and LICA 09 (Titanium IV 2,2(bis2-propenolatomethyl)butanolato, tris(dodecyl)benzenesulfonato-O); andcycloheteroatom titanates, such as KR® OPPR (Titanium IV bis octanolato,cyclo(dioctyl)pyrophosphato-O,O) and KR OPP2 (Titanium IV biscyclo(dioctyl)pyrophosphato-O,O). With the guidance provided herein, theskilled practitioner will be able to identify suitable titanates for usein embodiments of the disclosure.

The skilled practitioner recognizes that the layers, or pieces, also mayinclude further components such as fillers and/or additives. Fillers andadditives may be used based on any of a variety of desiredcharacteristics, such as enhancement of physical properties, UV lightresistance, and other properties. For example, to improve UV lightresistance, a light stabilizer is added. Light stabilizers may includehindered amines, UV stabilizers, or a mixture thereof.

Inorganic or organic fillers can be also added to any layer. Suitableinorganic fillers may include silicate minerals, metal oxides, metalsalts, clays, metal silicates, glass fibers, natural fibrous minerals,synthetic fibrous minerals or a mixture thereof. Suitable organicfillers may include carbon black, fullerene and/or carbon nanotubes,melamine colophony, cellulose fibers, polyamide fibers,polyacrylonitrile fibers, polyurethane fibers, polyester fibers based onaromatic and/aliphatic dicarboxylic acid esters, carbon fibers or amixture thereof. The inorganic and organic fillers may be usedindividually or as a mixture thereof. The total amount of the filler maybe from about 0.5 to about 50 percent by weight of the layer.

Other density adjusting agents, such as hollow beads that have a lowdensity, also may be used in selected layers.

The skilled practitioner recognizes that these additives, including inparticular the density adjusters, affect the performance properties andcharacteristics of the layer. Thus, the amount of any fillers may notexceed that amount that adversely affects the performance of the golfball.

Flame retardants may also be used to improve the flame resistance of anylayer, and particularly of thermoplastic polyurethane. Suitable flameretardants may include organic phosphates, metal phosphates, metalpolyphosphates, metal oxides (such as aluminum oxide hydrate, antimonytrioxide, arsenic oxide), metal salts (such as calcium sulfate,expandable graphite), and cyanuric acid derivatives (such as melaminecyanurate). These flame retardants may be used individually or as amixture thereof, and the total amount of the flame retardant may be fromabout 10 to about 35 percent by weight of a polyurethane component, forexample.

To improve toughness and compression rebound of thermoplasticpolyurethane elastomer, the thermoplastic polyurethane elastomer mayinclude at least one dispersant, such as a monomer or oligomercomprising unsaturated bonds. Examples of suitable monomers includestyrene, acrylic esters; suitable oligomers include di- andtri-acrylates/methacrylates, ester acrylates/methacrylates, urethane, orurea acrylates/methacrylates.

The outermost layer of a golf ball also may include at least one whitepigment to aid in better visibility. The white pigment may be selectedfrom the group consisting of titanium dioxide, zinc oxide or a mixturethereof.

With the guidance provided herein, the skilled practitioner will be ableto select additives for each layer or piece of the golf ball.

Examples

Nine golf ball cores were made and tested for selected performanceproperties and characteristics. The effects of process oil loading,process oil type, high Mooney viscosity polybutadiene rubber type, andfiller type were studied. The compositions of the golf ball cores was asfollows in Table 1, and the proportions and identities of the highMooney viscosity polybutadiene rubbers and process oils were as setforth in Table 2:

TABLE 1 Compositions of Golf Balls Recipe 1 2 Rubber, pounds 100 100Zinc diacrylate, phr 23.6 23.6 Zinc oxide, phr 23.2 6.5 Zinc stearate,phr 3 3 Barium sulfate, phr — 17 Dicumyl peroxide, phr 0.3 0.31,1-di(t-butylperoxy)3,3,5- 0.3 0.3 trimethylcyclohexane (TMCH), phr

TABLE 2 Golf ball core Proportions Golf Rubber Process Process oil BallRecipe type oil type amount, phr 1 1 BR1208 None 0 2 1 BR1208 Sunpar 1507.5 3 1 BR1208 Sunpar 150 15 4 2 BR1208 None 0 5 2 K60 None 0 6 2 K60 327.5 7 2 K60 32 15 8 2 K60 Sunpar 150 15 9 2 K60 Sunpar 2280 15

BR1208, available from LG Chem, has a Mooney viscosity of 40. K60 isKumho 60, available from Kumho. K60 has a Mooney viscosity of 60. Eachof the process oils is a paraffinic process oil.

The cores were prepared by curing the rubber for 8 minutes at 327° F.

Each of the golf ball cores was tested to determine Compression (ADCmachine), COR, and approximate weight. The results were summarized inTable 3, as follows:

TABLE 3 Performance properties and characteristics Golf CompressionWeight, ball core (ADC), mm COR grams 1 3.96 0.7832 39.5 2 4.99 0.755338.9 3 6.45 0.7278 38.5 4 4.12 0.7794 39.5 5 3.88 0.7889 39.3 6 4.980.7573 38.6 7 5.84 0.7401 38.3 8 6.09 0.7327 38.3 9 6.59 0.7221 38.3

As can be seen from this information, the increase in ADC compressionvalues as process oil loading increases, the reduction in COR as processoil loading increases, and the reduction in COR as ADC compressionincreases were essentially linear for each combination of process oiland high Mooney viscosity polybutadiene rubber type. Although theinventors do not wish to be bound by theory, performance decreases arethe consequence of the reduction in proportion, or dilution of therubber proportion, as process oil amount is increased. The volumepercent of rubber is 82.6 vol percent, 77.6 vol percent, and 73.2 volpercent, for 0 phr process oil, 7.5 phr process oil, and 15 phr processoil, respectively.

Additional properties and characteristics were determined for golf ballcores 1 and 4 to evaluate golf ball core properties and characteristicsfor different fillers. The results were summarized in Table 4 below. Theresults illustrated that the performance properties and characteristicsof the two golf ball cores are quite similar. Although the inventors donot wish to be bound by theory, it is believed that any differencesbetween the properties and characteristics of the two golf ball cores isthe result of differences in density and high Mooney viscositypolybutadiene rubber concentration, i.e., lower density and high Mooneyviscosity polybutadiene rubber concentration lead to lower COR andsofter compression.

TABLE 4 Comparison of performance properties and characteristics withdifferent fillers Golf ball core 1 4 Recipe 1 2 Rubber BR1208 BR1208Theoretical density, g/cm³ 1.1311 1.1264 Observed density, g/cm³ 1.161.15 Vol percent Rubber 82.65 82.13 COR 0.7832 0.7794 ADC Compression,mm 3.96 4.12

Additional examples or golf ball cores are prepared in accordance withembodiments of the disclosure. The performance properties andcharacteristics of each are as described in this disclosure. Each of thevalues in Table 5A is weight. Table 5B expresses amounts of peptizingagent in phr.

TABLE 5A Additional Examples Golf ball core 1 2 3 4 5 6 7 8 9 10 HighMooney viscosity 98 98 98 93.5 93.5 93.5 98 98 98 98 polybutadienerubber Aromatic process oil 2 6.5 Naphthenic process oil 2 6.5Paraffinic process oil 2 6.5 Epoxidized soybean oil 1.8 1.8 1.8 2 Amine0.2 Polyamide 0.2 Isocyanate 0.2 Total 100 100 100 100 100 100 100 100100 100

TABLE 5B Including Peptizing Agent Golf ball core 1 2 3 4 5 6 7 8 9 10Penta- 0.05 0.05 0.05 0.1 0.1 0.1 0.1 0.1 0.1 0.4 chlorothiophenol, phr

While various embodiments of the invention have been described, thedescription is intended to be exemplary, rather than limiting and itwill be apparent to those of ordinary skill in the art that many moreembodiments and implementations are possible that are within the scopeof the invention. Accordingly, the invention is not to be restrictedexcept in light of the attached claims and their equivalents. Forexample, different process oils, different high Mooney viscosityrubbers, and different proportions of oil and rubber may be used. Also,various modifications and changes may be made within the scope of theattached claims.

What is claimed is:
 1. A high performance golf ball comprising: amodified high Mooney viscosity rubber having less than about 20 poundsper 100 pounds of rubber (phr) of oil, the modified high Mooneyviscosity rubber comprising high Mooney viscosity rubber having a Mooneyviscosity at least about 40 blended with between about 1 phr and about10 phr of process oil and between about 0.05 phr and about 5 phr of apeptizing agent.
 2. The golf ball of claim 1, the golf ball furthercomprising a core layer, wherein the modified high Mooney viscosityrubber is in the core layer.
 3. The golf ball of claim 1, the golf ballfurther comprising an inner cover layer, wherein the modified highMooney viscosity rubber is in the inner cover layer.
 4. The golf ball ofclaim 1, wherein the high Mooney viscosity rubber is selected from thegroup consisting of polybutadiene rubber, polyisoprene rubber, naturalrubber, ethylene propylene rubber, ethylene propylene diene rubber,styrene-butadiene rubber, and blends thereof.
 5. The golf ball of claim4, wherein the high Mooney viscosity rubber is polybutadiene rubber. 6.The golf ball of claim 5, wherein the polybutadiene rubber comprisesgreater than about 90 percent cis structure.
 7. The golf ball of claim1, wherein the amount of the process oil is between about 2 phr andabout 7.5 phr.
 8. The golf ball of claim 1, wherein the process oil isselected from the group consisting of process oils, vegetable oils,vulcanized or functionalized vegetable oils, oils from animals,functionalized oils, and blends thereof.
 9. The golf ball of claim 8,wherein the process oil is selected from the group consisting ofnaphthenic oils, paraffinic oils, and blends thereof.
 10. The golf ballof claim 8, wherein the vulcanized or functionalized vegetable oils areselected from the group consisting of epoxidized soy bean oil,epoxidized linseed oil, epoxidized alkyl oils, the reaction products ofepoxidized oil with a peroxide, an amine, a polyamide, or anisocyanate-containing molecule, and blends thereof.
 11. The golf ball ofclaim 10, wherein the functionalized vegetable oil is epoxidized soybean oil.
 12. The golf ball of claim 4 wherein the peptizing agent ispentachlorothiophenol.
 13. The golf ball of claim 8 wherein thepeptizing agent is pentachlorothiophenol.
 14. The golf ball of claim 2,the golf ball further comprising an inner cover layer, wherein the innercover layer comprises HNP.
 15. The golf ball of claim 14, wherein theHNP is selected from the group consisting of HPF1000, HPF2000, HPFAD1024, HPF AD1027, HPF AD1030, HPF AD1035, HPF AD1040, and blendsthereof.
 16. The golf ball of claim 14, wherein the relative weightproportions of the modified high Mooney viscosity polybutadiene rubberto HNP in a blended product range from about 60:40 to about 99.5:0.5.17. The golf ball of claim 16, wherein relative weight proportions ofthe modified high Mooney viscosity polybutadiene rubber to HNP in ablended product range from about 75:25 to about 99:1.
 18. The golf ballof claim 2, wherein the golf ball further comprises a layer essentiallysurrounding the core, the layer comprising HNP.
 19. The golf ball ofclaim 2, wherein the core consists essentially of modified high Mooneyviscosity polybutadiene rubber and the layer consists essentially ofHNP.
 20. The golf ball of claim 3, the golf ball further comprising anouter cover, the outer cover comprising polyurethane.